1.7System memory

1.7.1 Overvi ew

The motherboard comes with four Double Data Rate 2 (DDR2) Dual Inline Memory Modules (DIMM) sockets.

A DDR2 module has the same physical dimensions as a DDR DIMM but has a 240-pin footprint compared to the 184-pin DDR DIMM. DDR2 DIMMs are notched differently to prevent installation on a DDR DIMM socket.

The figure illustrates the location of the DDR2 DIMM sockets:

P5ND2

 

B1 B2

DIMM A1 DIMM A2

DIMM

DIMM

Pins 112 Pins 128

P5ND2 240-pin DDR2 DIMM Sockets

Channel

Sockets

Channel A

DIMM_A1 and DIMM_A2

Channel B

DIMM_B1 and DIMM_B2

1.7.2 Memory confi gurati ons

You may install 256 MB, 512 MB, 1 GB, 2 GB and 4 GB unbuffered non-ECC DDR2 DIMMs into the DIMM sockets.

•For dual-channel configuration, the total size of memory module(s)

installed per channel must be the same

(DIMM_A1 + DIMM_A2 = DIMM_B1 + DIMM_B2).

•Always install DIMMs with the same CAS latency. For optimum compatibility, it is recommended that you obtain memory modules from the same vendor. Refer to the DDR2 Qualified Vendors List on the next page for details.

•If you install four 1GB memory modules, the system may only recognize

less than 3 GB because the address space is reserved for other critical functions. This limitation appears on Windows® XP 32-bit operation system which does not support Physical Address Extension (PAE).

•If you install Windows® XP 32-bit operation system, a total memory of less than 3GB is recommended.

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Chapter 1: Product introduction